1. Field of the Invention
The present invention relates to a resist removing liquid, a resist removal method using the same, and a method for producing a photomask.
2. Description of the Related Art
A circuit pattern has been transferred onto a silicon wafer by transmitting light such as a g-ray, an i-ray, an excimer laser, and the like from a high pressure mercury lamp, which has been used for exposure during semiconductor production, through a photomask. On the other hand, EUV light is absorbed by most materials. Therefore, a transmission type mask exposure technique of the related art cannot be employed and a method for forming a circuit pattern by reflecting light has been employed.
Specifically, the above-described EUV exposure is performed by using a reflection type mask employing a reflection projection optical system and making exposure light incident on the mask. The silicon wafer (semiconductor substrate) is irradiated with the light at a reflection angle which is equal to the incident angle. As described above, since the exposure methods are completely different from each other, the structure and the material of the photomask are significantly changed along with a change from a transmission type to a reflection type. In WO2009/116348A, there is disclosed a photomask for EUV exposure.